Dynamic radio configuration for seamless backhaul frequency optimization

ABSTRACT

Optimal determination of wireless network pathway configurations may be provided. A computing device may detect, at a first network Access Point (AP), inference on a channel with a second AP. Then, the computing device can check availability of a redundant radio at the second AP. Based on the availability, the computing device can establish a new radio link with the redundant radio at the second AP and reroute data traffic over the new radio link to the second AP. After establishing the new radio link, the computing device can then sever the channel with the second AP.

TECHNICAL FIELD

The present disclosure relates generally to wireless networks.

BACKGROUND

In computer networking, a wireless Access Point (AP) is a networkinghardware device that allows a Wi-Fi compatible client device to connectto a wired network and to other client devices. The AP usually connectsto a router (directly or indirectly via a wired network) as a standalonedevice, but it can also be an integral component of the router itself.Several nodes may also work in coordination, either through direct wiredor wireless connections in a Wireless Local Area Network (WLAN). Theconnections between the APs in the WLAN may be referred to as wirelessmesh backhaul links. Sometimes it is necessary to change theconfiguration of these wireless mesh backhaul links.

The WLAN wireless spectrum is typically separated into distinct radiofrequency ranges, which may also be further divided into a multitude ofchannels. Channels can be affected by interference, which may requirethe APs to switch to another channel. However, channel changes can be avery disruptive process, and the channel changes can be even moredisruptive when the channel that needs changing is on the mesh backhaulradios.

BRIEF DESCRIPTION OF THE FIGURES

The accompanying drawings, which are incorporated in and constitute apart of this disclosure, illustrate various example(s) of the presentdisclosure. In the drawings:

FIG. 1A is a block diagram of wireless network environment in accordancewith aspects of the present disclosure;

FIG. 1B is another block diagram of wireless network environment inaccordance with aspects of the present disclosure;

FIG. 1C is another block diagram of wireless network environment inaccordance with aspects of the present disclosure;

FIG. 1D is another block diagram of wireless network environment inaccordance with aspects of the present disclosure;

FIG. 1E is another block diagram of wireless network environment inaccordance with aspects of the present disclosure;

FIG. 1F is another block diagram of wireless network environment inaccordance with aspects of the present disclosure;

FIG. 1G is another block diagram of wireless network environment inaccordance with aspects of the present disclosure;

FIG. 1H is another block diagram of wireless network environment inaccordance with aspects of the present disclosure;

FIG. 2 is a block diagram of an AP or other network node device inaccordance with aspects of the present disclosure;

FIG. 3 is a flow chart of a method for changing the frequency bandand/or the channel of a wireless mesh backhaul in accordance withaspects of the present disclosure;

FIG. 4 is another flow chart of a method for changing the frequency bandand/or the channel of a wireless mesh backhaul in accordance withaspects of the present disclosure;

FIG. 5 is another flow chart of a method for changing the frequency bandand/or the channel of a wireless mesh backhaul in accordance withaspects of the present disclosure;

FIG. 6A is a block diagram of a computing device in accordance withaspects of the present disclosure; and

FIG. 6B is a block diagram of an AP or other networking device inaccordance with aspects of the present disclosure.

DETAILED DESCRIPTION Overview

Optimal determination of wireless network pathway configurations may beprovided. A computing device may detect, at a first node, e.g., a firstAP, inference on a channel with a second AP. Then, the computing devicecan check availability of a redundant radio at the second node, e.g., asecond AP. Based on the availability, the computing device can establisha new radio link with the redundant radio at the second AP and reroutedata traffic over the new radio link to the second AP. Afterestablishing the new radio link, the computing device can then sever thechannel with the second AP.

Both the foregoing overview and the following description are examplesand explanatory only, and should not be considered to restrict thedisclosure's scope, as described and claimed. Furthermore, featuresand/or variations may be provided in addition to those described. Forexample, example of the disclosure may be directed to various featurecombinations and sub-combinations described in the example.

Example

The following detailed description refers to the accompanying drawings.Wherever possible, the same reference numbers are used in the drawingsand the following description to refer to the same or similar elements.While example(s) of the disclosure may be described, modifications,adaptations, and other implementations are possible. For example,substitutions, additions, or modifications may be made to the elementsillustrated in the drawings, and the methods described herein may bemodified by substituting, reordering, or adding stages to the disclosedmethods. Accordingly, the following detailed description does not limitthe disclosure. Instead, the proper scope of the disclosure is definedby the appended claims.

A WLAN can be formed from two or more nodes. The nodes will be describedhereinafter as APs, but, the aspects herein are not limited to APs, asthe nodes may be other types of network devices. The connections betweenAPs form a wireless backhaul where data can be communicated through theWLAN before being sent from an AP to a client. In the aspects describedherein, the APs can monitor the backhaul links to determine if thesebackhaul links are suffering from interference. If the AP detectsinterference at the receiver, the backhaul channel may need to bechanged to eliminate or mitigate the interference and continue orimprove performance. The channel can be changed at the Rooftop AP (RAP),which may function as a main or controller AP, and for the radios on thedependent APs, referred to as Mesh APs (MAP).

In some circumstances, the interference may be detected at the RAP. Dueto the interference, the APs may change the channels at the RAP and anydependent MAPs. Another dependent MAP may be linked to one of the MAPsthat will have the channel changed. However, the channel to that otherdependent MAP may not need to be changed because the channel to thatother dependent MAP may not be detecting interference at any of theradios. To go through the channel change, the RAP and MAP(s) maycomplete one of three possible processes.

In a first process, the RAP and/or MAP(s) can find and check thecandidate radio interface that is redundant and available at thedependent MAP mesh radios. For example, the APs may find that both the2.4 GHz and the 6 GHz interfaces are available at the dependent MAPradios. The 6 GHz radio can be selected as the candidate radio, and theRAP may send beacons (e.g., Adaptive Wireless Path Protocol (AWPP)beacons) and configure the radios on the RAP and/or MAP(s) for thetarget channel change.

The choice of the radio can be based on requirements for the meshnetwork, for example, the network may be servicing many 2.4 GHz capableclients at the APs but may not have any or many 6 GHz clients. Thus, the2.4 GHz radio may be chosen. This decision as to which radio to choosecould also be based on the amount of traffic load on the backhaul and/orthe type of traffic. For example, if the load on the backhaul is low andmost of the traffic is locally terminating at the mesh nodes, the RAPmay choose the 2.4 GHz radio as the candidate radio interface.

Once the new candidate radio is established, the RAP and/or MAPs canestablish and then start re-routing the mesh backhaul over the new radiolink. After re-routing, the RAP and/or MAPs can sever theinterference-prone mesh link or change the channel on that radio linkand switch back to that radio link. When the channel change is done withthese APs, the network may also make a routing change for the networksegments beyond the initial APs. Thus, these other APs may daisy-chainthe data. In the example above with the other dependent MAP, the networkmay have decided that the backhaul link for this other dependent MAP didnot need to be changed. Rather, the MAP connected to the RAP can ensuredownstream packets, from the RAP and sent over the link that underwentthe channel change, are received and daisy-chained over the other radiolink down to other dependent MAP(s), as before. In other words, thechannel is not changed to the other dependent MAP but data is reroutedto the old link, to the other dependent MAP, from the changed link.

Optionally, as a part of the method above, the RAP can change thechannel on the original radio interface, e.g. the 5 GHz radio, and movethe connection back to that interface. It is important to note that thenetwork re-configuration can also be driven by a controller or any otherentity on the network. The method presented above has many advantages.The change is a seamless channel change, and the APs may never loseconnectivity on the backhaul. All the connections above follow amake-before-break approach to ensure persistent connectivity.

As explained above, the candidate redundant radio choice may be based onthe type of traffic load, for example, the amount of local trafficcompared to the amount of backhaul traffic. The type of traffic can beevaluated during startup or after an initial configuration is applied.The MAPs can track the amount of incoming traffic that is being sentlocally over the WLAN between clients (identified as T1 traffic) ascompared to the amount of traffic sent to the backhaul (identified as T2traffic). Similarly, the APs can also measure the amount of trafficcoming from the backhaul destined for the clients (identified as T3traffic) compared to the amount of traffic locally generated anddestined for local clients (identified as T4 traffic). The APs cancalculate a ratio which indicates the relative Backhaul traffic loadversus local traffic load at every MAP. The algorithm for thiscalculation is:

LoadRatio(AP(i))=(T2+T3)/(T1+T4)

If the LoadRatio(MAP(i)) is greater than 1, the ratio indicates that theAPs need to configure the faster radios for the backhaul compared toclient serving. For example, if the LoadRatio(MAP(i)) is greater than 1,the APs may prefer to configure the 5 GHz or 6 GHz radios for thebackhaul rather than the 2.4 GHz.

The second process for conducting the channel change may addressMulticast Listener Device (MLD)-oriented dynamic daisy-chaining. Atypical MLD operates with two or more radios that work together toachieve a single high-performance Media Access Control (MAC) link. In anexample, there are two links, a first link on channel X and a secondlink on channel Y. The channel change condition under consideration canapply to both Simultaneous Transmit and Receive (STR) and non-STR MLDbased backhaul links.

In an implementation, the AP can determine which dependent MLD radiosmay need a channel change. The AP may then detach the MAC Service AccessPoint (SAP) from the radios subject to the channel change. For example,to change the channel for the 5 GHz radio, the AP can detach the MAC SAPfrom the 5 GHz radios and bind the MAC SAPs to the 6 GHz radio. The APcan then dynamically send backhaul traffic to a single link in the MLD,for example, connect the MAC SAP to a single radio. Then, the AP canchange the channel on the 5 GHz radio and re-attach the MAC SAP acrossboth radios. The AP can then reset the sequence numbering at the MAClevel to avoid any out-of-order packets.

The third process can address dynamic daisy-chaining for coalescedradios. Radio coalescing is a mechanism by which two or more radios are“merged” into one for the purpose of improving performance. For example,the AP can combine two 4×4 Irons into a single 8×8 MAC interface. Acoalesced radio can provide higher throughput compared to a single 4×4radio.

First, the AP can decide that a channel change may be required on a meshlink that has a coalesced radio interface. In a first stage, both theradios, at the two APs, may be coalesced into 8×8 radio(s) and operatingover channel X. The AP can decouple the MAC SAP on the radios and limitpackets from both sides to a 4×4 mode. Then, with the radios split andoperating as two independent net devices, the AP can proceed to changeto the target channel Y, as described above. Once the radios havediscovered and connected to each other on channel Y, the AP can severthe link on the channel X radios. Then, the AP can also change thechannel on the unused radios to the new channel Y. Finally, the radioscan be coalesced back into a single MAC instance for operation in the8×8 mode.

The above example proposes a channel change with the radio gettingcoalesced from two 4×4 antenna configuration to an 8×8 configuration.However, the process can be extended to other radio configurations. Forexample, a similar approach would work if one end of the mesh link has acoalesced radio while the other node does not use a coalesced radio.

The processes above have several advantages. The switch to a new channelon the backhaul link is seamless, for example, there is no loss ofconnectivity and there is zero outage. The processes can be triggered onother events, for example, channel changes, radar and/or radio resets,any other outages, and/or noise and interference at the receiver. Thenetwork re-configuration can be automatic for the administrator andkeeps management simple. Finally, if the number of radios increases perAP, the processes above can manage the network while simplifying thedesign of the AP and/or network.

A wireless environment 100 may be as shown in FIG. 1. The wirelessenvironment 100 can include a wireless local area network 101, which caninclude two or more nodes, e.g., APs 102. The wireless network 101 canbe controlled by a controller 103, e.g., a Wireless Local Area Network(WLAN) controller (WLC), a network controller, etc. The AP 102, or otherdevices, and the controller 103 may be computer systems or other devicesas described in conjunction with FIGS. 6A and 6B.

The one or more APs 102/104 may form a wireless network 101, forexample, a wireless mesh network. The wireless network 101 may becomposed of two or more APs 102/104. The APs 102/104 can join and/orcommunicate together to form a wireless backhaul, which may be capableof communicating data from one client to another. The wireless backhaulmay be formed by one or more links between the APs, as may be shown inFIGS. 1A-1H. For example, an ingress AP 102/104 a may communicateinformation or data to an egress AP 102/104 d from one client,communicating with the ingress AP 102/104 a, to another client,communicating with the egress AP 106 d. However, AP 102/104 a may notcommunicate directly with AP 102/104 d. As such, the AP 102/104 a mayform one or more wireless backhaul links to communicate data through oneor more intermediary APs 102/104 between AP 102/104 a and AP 102/104 d.For example, there may be a wireless backhaul segment from AP 102/104 ato AP 102/104 b, then to AP 102/104 c, and finally to AP 102/104 d.These track segments may communicate over a radio channel.

The WLAN may be controlled by a controller 103, e.g., a WLC. Thecontroller 103 can communicate with the one or more APs 102/104 withinthe WLAN 101. The controller 103 can receive information about linkerrors from the one or more APs 102/104. Further, the controller 103 candetermine how to change a channel on a radio interface to address thelink errors. Thus, the processes, etc., described herein can beconducted by the AP 102/104 and/or by the controller 103.

Various types of wireless links may be implemented by the wirelessnetwork 101, as may be shown in FIGS. 1B through 1H. The APs 102/104 a,112, 114, and/or 118 may configure links and/or radio channels to avoiderrors or interference. Representations of one or more wireless backhaullink(s) may be implemented between an ingress AP 102/104 a and an egressAP 102/104 b, as may be shown in FIGS. 1B-1H. The wireless network 101can include a Rooftop AP (RAP) 102 and one or more Mesh AP(s) (MAP) 104.In implementations, the RAP 102 may function to control functions of theMAPs 104.

In an example, there may be one or more errors occurring in one or moreAPs 102/104 or link segments between the APs 102/104. These errors maymake communication between the APs 102/104 difficult or impossible, ormay affect data quality or service quality. Regardless, the errors mayrequire a rerouting of the data traffic between the APs 102/104 of thewireless network 101, as shown in FIGS. 1B-1H.

As stated above and as shown in FIG. 1A, wireless network 101 maycomprise Wi-Fi APs 102/104 (e.g., first AP 102/104 a and/or second AP102/104 b) that may be configured to support a wireless (e.g., Wi-Fi)network 101. The APs 102/104 may comprise a physical location where auser, operating client device, may obtain access to a wireless network101 (e.g., Internet access), using Wi-Fi technology, via a WLAN using arouter connected to a service provider.

In other example(s) of the disclosure, rather than APs, devices may beused that may be connected to a cellular network that may communicatedirectly and wirelessly with end use devices (e.g., a client device) toprovide access to wireless network 101 (e.g., Internet access). Forexample, these devices may comprise, but are not limited to, eNodeBs(eNBs) or gNodeBs (gNBs). The aforementioned cellular network maycomprise, but is not limited to, a Long Term Evolution (LTE) broadbandcellular network, a Fourth Generation (4G) broadband cellular network,or a Fifth Generation (5G) broadband cellular network, operated by aservice provider. Notwithstanding, example of the disclosure may usewireless communication protocols using, for example, Wi-Fi technologies,cellular networks, or any other type of wireless communications.

Client devices (not shown) may comprise, but are not limited to, aphone, a smartphone, a digital camera, a tablet device, a laptopcomputer, a personal computer, a mobile device, a sensor, anInternet-of-Things (IoTs) device, a cellular base station, a telephone,a remote control device, a set-top box, a digital video recorder, acable modem, a network computer, a mainframe, a router, or any othersimilar microcomputer-based device capable of accessing and using aWi-Fi network or a cellular network.

The elements described above of wireless network 101 (e.g., WLC 103,first AP 102/104 a, second AP 102/104 b, etc.) may be practiced inhardware, in software (including firmware, resident software,micro-code, etc.), in a combination of hardware and software, or in anyother circuits or systems. The elements of wireless network 101 may bepracticed in electrical circuits comprising discrete electronicelements, packaged or integrated electronic chips containing logic gates(e.g., Application Specific Integrated Circuits (ASIC), FieldProgrammable Gate Arrays (FPGA), System-On-Chip (SOC), etc.), a circuitutilizing a microprocessor, or on a single chip containing electronicelements or microprocessors. Furthermore, the elements of wirelessnetwork 101 may also be practiced using other technologies capable ofperforming logical operations such as, for example, AND, OR, and NOT,including but not limited to, mechanical, optical, fluidic, and quantumtechnologies. As described in greater detail below with respect to FIGS.6A and 6B, the elements of wireless network 101 may be practiced in acomputing device 600 and/or wireless device 630.

An implementation of the different hardware, software, or combination ofhardware software for the AP 102/104 and or the controller 103 may be asshown in FIG. 2. The device 200 may represent one or more of the APs102/104 or the controller 103, described in conjunction with FIGS. 1Athrough 1H. The device 200 can include one or more of, but is notlimited to, an interference determiner 202, a candidate radiointerference checker 204, a radio configurer 206, a radio re-router 208,a radio severer 210, a dependent radio re-router 212, and/or a coalescedradio interface 216. The device 200 may be a computer device orcomputing system implementation 600, as described in conjunction withFIGS. 6A and 6B.

The interference determiner 202 can detect, measure, or analyze aninterface between an RAP 102 and one or more MAPs 104 and/or between oneMAP 104 and another MAP 104. The interference determiner 202 can measureQuality Of Service (QOS) indicators, for example, data loss, packetdelays, or other types of measures and metrics to determine if there isinterference on an existing radio channel/interface. The interferencedeterminer 202 can detect interference on a single radio interface 106or on multiple radios 106 a through 106 c. For example, the interferencedeterminer 202 can monitor the active radio, e.g., radio 106 c, which iscurrently sending or receiving data. If interference is detected orcrosses some threshold for the active radio 106 c, the interferencedeterminer 202 can send the interference indication and/or informationto the radio configurer 206.

The candidate radio interference checker 204 can check for interferenceon unused radio interfaces. For example, if the 5 GHz radio 106 c iscurrently being used as shown in FIG. 1B, the candidate radiointerference checker 204 may check the 6 GHz radio 106 b or the 2.4 GHzradio 106 a to determine if there is interference in those signals beingreceived by or sent to other APs 102/104 or may check for interferenceby measurement of the WLAN environment 101. The candidate radiointerference checker 204 can then pass this interference information tothe radio configurer 206 to determine if a switch to a different radiomay help improve the QOS, improve other types of measurements, orimprove the service to the clients. Further, the candidate radiointerference checker 204 may also check the dependent APs, for example,MAP 104 c, and MAP2 104 a, to determine if the other redundant radios onthose APs 104 are both available and also not being affected byinterference or some other type of degradation. This checking may occurby message exchange between the RAP 102 and MAPs 104. In otherimplementations, the RAP 102 can determine a configuration of the MAP(s)104 based on an exchange of data packets or control signals, or othertypes of measures or information.

The radio configurer 206 can configure a candidate radio interface toswitch to and prepare that radio interface for changes to route thetraffic between APs 102, 104. The radio configurer 206 can prepare, forexample, the 6 GHz radio 106 b to take or assume data traffic from the 5GHz radio 106 c, for example. The radio configurer 206 can configure the6 GHz radio to begin accepting or sending data or doing other types ofactions to reroute the data signal. Further, the radio configurer 206can direct or can instruct the MAPs 104 also to configure their radiointerfaces, such that a link is established between the RAP 102 andMAP(s) 104 over the new radio link.

The radio re-router 208 can then begin to reroute signals over the newinterface. The previous radio interface may include a queue that can bechanged or rerouted to send the queued signals to the new radiointerface. For example, any type of messages that are to be sent overthe 5 GHz radio 106 a may then be routed to the newly established linkover the 6 GHz radio 106 b. For example, as shown in FIG. 1C, the linkof the 5 GHz radio 108 a, 108 b may be maintained, but as data is to besent over the 5 GHz radio, the data can be rerouted to the 6 GHz radioto send over link 110 a, 110 b. The radio re-router 208 determines whenthe 5 GHz radio 106 c queue has completed sending data. Once completed,the radio re-router 208 can send the completion information to the radioseverer 210.

The radio severer 210, upon completion of the final data or messagesbeing sent over the 5 GHz radio 106 a, may sever the link 108 a, 108 bto the dependent MAPs 104. Thus, the 5 GHz connections are eliminated,as shown in FIG. 1D. At that point, the connection between the RAP 102and MAP(s) 104 is only over the 6 GHz radio 106 b. Thus, the radioseverer 210 ensures that the old link is only severed upon theestablishment of the new link 110.

The dependent radio re-router 212 can instruct the dependent radios 106to insure rerouting of the data signals at those dependent MAPs 104. Forexample, the dependent radio re-router 212, of the RAP 102, can sendinstructions to the MAPs 104 a, 104 c to complete the link 110 a, 110 bto the newly configured 6 GHz radio interface. In this way, the RAP 102can instruct the dependent MAPs 104 a, 104 c to change routing to thenewly establish radio link while still maintaining the old radio link108 a, 108 b (as shown in FIG. 1C), before the MAPs 104 a, 104 cdisconnect or discontinue the old radio link 108 a, 108 b after the newradio interface link 110 a, 110 b has been established.

To establish the rerouting, the radio configurer 206 of the RAP 102 maysend beacons (e.g., Adaptive Wireless Path Protocol (AWPP)) to begin theconfiguration of the channel change. The radio configurer 206 can alsochoose which radio to switch to based on the responses to the beacons.The radio configurer 206 can choose which radio to use based on theclients being serviced and types of connections and/or data beingexchanged between the RAP 102 and MAPs 104 and/or between MAPs 104.

This radio decision may also be based on the model load on the backhaul.The model may determine if the load on the backhaul is low (e.g., at orbelow a predetermined threshold, for example, 30%, of the maximumpossible bandwidth and/or data capacity). Further, the model can comparethe traffic terminations to a predetermined threshold to determinewhether that traffic is mostly terminated at the MAPs 104 (e.g., 90% ofthe traffic is terminated at the MAPs 104 (other thresholds arepossible)). Further, the model can compare the traffic terminations toanother predetermined threshold to determine whether that traffic isusing the backhaul for internetwork transmissions at the MAPs 104 (e.g.,30% of the traffic sending traffic to other networks (other thresholdsare possible)). Based on the information determined in the wirelessnetwork 101, the model can determine the radio interface to which toswitch. For example, if the traffic is low and/or the traffic is beingterminated mostly at the MAPs 104, the radio configurer 206 may choosethe 2.4 GHz radio 106 a, as a better use of bandwidth.

Further, the dependent MAPs, e.g., MAP2 104 a, may have furtherconnection(s) to other dependent MAP(s), e.g., MAP3 104 b. These furtherlinks, e.g., 108 c, may require further channel changes or otherconfigurations. For example, if the 5 GHz link 108 c between MAP 104 aand MAP 104 b is not subject to interference, then the 5 GHz radiointerface link 108 c can be maintained. Thus, any data coming from the 6GHz radio link 110 b into MAP2 104 a may need to be rerouted, from the 6GHz radio 106 b to the 5 GHz radio 106 c, in MAP2 104A. Theseconfigurations above can be made by the dependent radio re-router 212 onRAP 102 or on MAP2 104 a. In this way, the links from the 6 GHz radio106 b to the 5 GHz radio 106 c are daisy-chained from the RAP 102, tothe MAP2 104, and then to the MAP3 104 b. This daisy-chaining, usingdifferent radio interfaces 106, allows for optimizing radio links (e.g.,eliminating interference-prone links) while not needing to change linksthat are not being affected. Thus, the total network configuration isoptimized for ensuring quality of service.

It should be noted that it is possible to change the channel on anoriginal radio link and then move back to the original interfaceconnection after the channel change. Further, the RAP 102 and MAP(s) 104may make the channel changes or the changes may be made by a controller103. Regardless, the connections are a make-before-break configuration.For example, the switch to the 6 GHz radios 106 b, explained above,occurs but the old 5 GHz link 108 is not eliminated or severed until theswitch to the 6G radio 106 b is completed. This process mitigates issueswith a drop in service that clients could see with other types of radiolink changes.

The radio re-router 208 can evaluate the redundant radios and whichlink(s) to use based on whether the traffic load is either local or onthe backhaul. Thus, for example, the MAPs 104 can track the amount ofincoming traffic that is either being sent locally to the client(s)compared to the amount of traffic that is being sent to the backhaul. Aratio of backhaul traffic load to local load may be computed. The RAP102 or MAP(s) 104, for example, can solve an algorithm:LoadRatio(MAP(i))=(T2+T3)/(T1+T4). In the algorithm, T1 is the amount ofincoming traffic that is being sent locally over the WLAN 101; T2 is theamount of traffic sent to the backhaul. Further, T3 is the amount oftraffic coming from the backhaul destined for the clients, and T4 is theamount of traffic locally generated and destined for the clients. If theLoadRatio is greater than one, then there is more backhaul traffic thanlocal traffic, and a configuration to the faster radios, for example,the 6 GHz radio 106 b, is warranted. However, if the LoadRatio is lessthan one and there is more local traffic than backhaul traffic, then aconfiguration to a lower speed interface, for example, the 2.4 GHz radio106 a, may be more appropriate.

The coalesced radio interface 216 may allow for switching of thechannels when coalesced radios are being employed. Coalesced radios areseparate radios that can be combined into one radio having morebandwidth. These coalesced radios need to be severed or broke intoindependent radios before switching channels. The coalesced radiointerface 216 can complete the instructions for such switching ofcoalesced radios.

Referring now to FIG. 3, a method 300 may be shown for switching radiochannel interfaces or links in an wireless environment 100. The method300 may be explained in conjunction with FIGS. 1B through 1D. The method300 can start with a start operation and can end with an end operation.The method 300 can include more or fewer stages or can arrange the orderof the stages differently than those shown in FIG. 3. The method 300 canbe executed as a set of computer-executable instructions, executed by acomputer system or processing component, and be encoded or stored on astorage medium. Further, the method 300 can be executed by a gate orother hardware device or component in an ASIC, a FPGA, a SOC, or othertype of hardware device. Hereinafter, the method 300 shall be explainedwith reference to the systems, components, modules, software, datastructures, etc. described herein.

In an implementation, the RAP 102 can detect interference on a channelconnected to an MAP 104, in stage 302. The interference determiner 202can determine if there is some type of interference or degradation inthe link(s) 108 between the RAP 102 and MAP(s) 104. For example, theremay be degradation on link 108 b between the 5 GHz radios 106 c on thelink between RAP 102 and MAP 104 c. The interference can include a lossof data, a degradation in the QOS measures, or some other type of issuewith the link 108 b to MAP 104C. Other links, e.g., 108 a, 108 c mayalso be evaluated by the RAP 102 and/or MAP(s) 104 a, 104 b, and/or 104c.

The RAP 102 may then check whether a redundant radio may be available atthe MAP(s) 104, in stage 304. The candidate radio interference checker204 may check and/or determine if another radio, for example, the 6 GHzradio 106 b, may be available and can be connected to the MAP(s) 104from the RAP 102. For example, the connection to the 6 GHz radio 106 bmust be available at both the MAP1 104 c and MAP2 104 a. As such, thecandidate radio interference checker 204 can determine if the 6 GHzradio 106 b is available at the MAP 104 by signals being sent to the MAP104 or an exchange of communications or other data packets between theRAP 102 and the MAPs 104 c, 104 a. The candidate radio interferencechecker 204 can also determine if any type of data loss or signaldegradation may be occurring in the 6 GHz radio 106 b, or othercandidate radio, based on other traffic being sent to the RAP 102.

The RAP 102 may then choose the radio for the channel change, in stage306. For example, the radio configurer 206, of the RAP 102, candetermine (if the 5 GHz radio 106 c is currently being used) whether the2.4 GHz radio 106 a or the 6 GHz radio 106 b is to be chosen forcommunications between the RAP 102 ad MAP(s) 104 a, 104 c. Thedetermination of the candidate radio may be based on the LoadRatio, asdescribed above, which may be based on the load characteristics of, orthe type traffic being communicated at, the RAP 102 and/or MAP(s) 104.Depending on the solution of the LoadRatio, as described before, theradio configurer 206 can determine which radio to establish as a newradio interface.

The RAP 102 may then establish the new radio interface with MAPs 104, instage 308. The radio configurer 206 may send beacons, other signals, ordata packets between the RAP 102 and the MAP 104 to establish the newradio link 110. These packets or beacons may instruct the MAP 104 toswitch to the new radio, for example, to the 6 GHz radio 106 b. Once thenew radios links 110 a, 110 b are established between the RAP 102 andthe MAPs 104 a and 104 c, the data traffic may begin to be rerouted tothat new radio interface at both the RAP 102 and the MAPs 104 a and 104c. The previous channel and the new radio link are in differentfrequency bands.

The RAP 102 may then reroute traffic, for example from a data queueassociated with the old radio, for example, the 5 GHz radio 106 c, tothe new radio interface, for example, the 6 GHz radio 106 b, in stage310. The radio re-router 208 can now reroute data, from a queue of datapackets or signals, which are being sent over old radio, for example,the 5 GHz radio 106 c, to the new radio interface, e.g., the 6 GHz radio106 b, to be sent over links 110. The radio re-router 208 changes thedata packets or performance of the radios 106 inside the RAP 102, andMAPs 104 to empty the queue on the old radio interface, e.g., the 5 GHzradio interface 106 c.

After rerouting is established, the RAP 102 can sever the interferenceprone link, in stage 312. For example, after the radio re-router 208completes rerouting traffic through the new radio link 110 a, 110 b, theradio severer 210 can sever or discontinue the links 108 a, 108 b on theold 5 GHz radio interfaces 106 c. Thus, the new link 110 is establishedbefore the elimination or teardown of the other link 108. In this way,no data is lost during the establishment of the new radio link 110, andthe clients are unaware of the switching between the radio interfaces106.

The RAP 102 may then instruct the one or more MAP(s) 104, to reroute orchange traffic over a daisy-chained link from the MAP 104 to another MAP104, in stage 314. The dependent radio re-router 212, of the RAP 102,can send instructions to the MAP(s) 104 to change the routing of trafficat the MAP(s) 104. For example, the dependent radio re-router 212 cansend instructions to MAP2 104 a to change the link 108 c between MAP2104 a and MAP3 104 b. However if there is no interface interference overlink 108 c, the MAP2 104 a may disregard the instructions and continueto use the radio link 108 c over the 5 GHz interface 106 c. If the link108 c is not experiencing interference, the MAP2 104 a may communicateas such to the RAP 102, which will not send instructions, as above, inresponse. In these situations, MAP2 104 a may be instructed to routetraffic from the new interface, e.g., the 6 GHz interface 106 b, fromthe RAP 102 to MAP2 104 a, to the existing link 108 c, on the 5 GHzinterface 106 c that communicates to MAP3 104. In other situations, theMAP2 104 a may change the link 108 c to the 6 GHz link between MAP2 104a and MAP3 104 b. The MAP3 104 b may have the same or similar componentsas is shown in FIG. 2, to help change the link between the two MAP(s)104 a, 104 b.

Another implementation of a method 400 for changing the radio interfacesbetween devices may be as shown in FIG. 4. The method 400 may beexplained in conjunction with FIGS. 1E and 1F. The method 400 can startwith a start operation and can end with an end operation. The method 400can include more or fewer stages or can arrange the order of the stagesdifferently than those shown in FIG. 4. The method 400 can be executedas a set of computer-executable instructions, executed by a computersystem or processing component, and be encoded or stored on a storagemedium. Further, the method 400 can be executed by a gate or otherhardware device or component in an ASIC, a FPGA, a SOC, or other type ofhardware device. Hereinafter, the method 400 shall be explained withreference to the systems, components, modules, software, datastructures, etc. described herein.

Multicast Listener Discovery (MLD) devices, e.g., devices 112 and 114,may use multiple links, e.g., links 116 a and 116 b, to send and receivedata. These dual links 116 may be over different radios, e.g., a 2.4 GHzradio 116 a and a 5 GHz radio 116 b. One or both of these links couldsuffer from interference or other issues.

An example of two MLD devices 118 a, 118 b, which may use multiplebands/channels 128, 130, and/or 132 for the backhaul, is as shown inFIGS. 1E and 1F. The method 400 can work for both simultaneous transmitand receive (STR) and non-STR MLD devices. The MLD devices 118 may betransmitting over the backhaul link on both a first channel 128 and asecond channel 130, with an MLD link 132 providing administrativecommunications.

The RAP MLD 118 a may determine that the dependent radios are sufferingfrom interference, in stage 402. Here, the interference determiner 202can determine that one of the channels or both channel interfaces 120 a,120 b, 122 a, and/or 122 b are suffering from interference. Thecandidate radio interference checker 204 can then determine whichdependent MLD radios 120 need to have a channel change. For example, thecandidate radio interference checker 204 can determine whether the link128, e.g., from the 5 GHz radio interface, should be changed to adifferent radio link.

The radio configurer 206 of the RAP MLD 118 a may detach the MediaAccess Control (MAC) layer Service Access Point (SAP) 124 and or 126from the radio suffering from interference, in stage 404. The radioconfigurer 206 can detach the SAP from the link, e.g., link 128, havinginterference issues to transfer or bind that MAC SAP to another radio.The radio configurer 206 may then bind the MAC SAP to the other, radio,in stage 406. For example, the link 128, over the 5 GHz radio, may bechanged from the RAP 102 to an MAP 104 and the SAP is bound only to link130.

The RAP 102 may then dynamically send traffic from the RAP 102 to theMAP 104 over the signal MLD link, e.g., link 130, in stage 408. Forexample, the two channels 128, 130 may be reduced to the sing link 130,and link 128 may see the SAP removed. This change may bound the devices118 to the other radio 120 b, 122 b, for example, the 6 GHz radio 106 b.This binding may establish a single MLD Link 130 and/or 132 between thetwo MLD devices 118 a, 118 b.

The radio re-router 208, of the RAP 102, may then change the channel onthe old radio, e.g., the 5 GHz radio 106 c, in stage 410. The radiore-router 208 may then change the channel on the radio havinginterference or may change to a different band, e.g., the 2.4 GHz radio,after establishing a single MLD link 130. Thereinafter, the RAP 102 maythen reattach the MAC SAP across both radios, in stage 412. The radiore-router 208 can then reattach the SAP to both radios. The radiore-router 208 can change the channel and reattach the MAC SAP acrossboth radios to reset the sequencing number at the MAC level to avoid anyout of order packets. In this way, the radio interface for the MLDdevices is dynamically changed between RAP 102 and MAPs 104.

An implementation of a method 500 for switching the radio interfacesacross AP(s), with at least one AP with a coalesced radio, may be asshown in FIG. 5. The method 500 may be as described in conjunction withFIGS. 1G and 1H. The method 500 can start with a start operation and canend with an end operation. The method 500 can include more or fewerstages or can arrange the order of the stages differently than thoseshown in FIG. 5. The method 500 can be executed as a set ofcomputer-executable instructions, executed by a computer system orprocessing component, and be encoded or stored on a storage medium.Further, the method 500 can be executed by a gate or other hardwaredevice or component in an ASIC, a FPGA, a SOC, or other type of hardwaredevice. Hereinafter, the method 500 shall be explained with reference tothe systems, components, modules, software, data structures, etc.described herein.

The RAP 102 may determine that dependent radio interference isoccurring, in stage 502. The interference determiner 202 may determinethat one or more radio interfaces is suffering from interference orother issues. The interference determination may then be sent to thecandidate radio interference checker 204 and/or the radio configurer 206to determine whether a channel should be changed to a new radio.

The interference determiner 202 can determine the channel, as shown instage #0, 136, of FIG. 1G, suffers from interference and may need to beswitched between radios 148 a and 148 b on the two separate APs. Theradio configurer 206 may then go through a process to decouple thecoalesced radios.

For example, the RAP 102, and or MAP 104, may detach the MAC SAP fromthe radios 148, in stage 504. The radio configurer 206 can detach theMAC SAP from the coalesced radios of the MAP 104 and/or RAP 102. Then,the radio configurer 206 may then limit traffic from the RAP 102 or tothe RAP 102 from the MAP 104 to a single link 151, in stage 506. Trafficis limited to first decouple or change the coalesced radios.

The RAP 102 may then split the coalesced radios and change to the targetchannel on one side of the radios, in stage 508. For example, thecoalesced radio interface 216 may change the coalesced radios, as shownin stage #1 138 of FIG. 1G. Here, the channel 151 is now only betweenone 4×4 radio, on the RAP 102, and the same 4×4 radio on the MAP. Thus,the coalesced radios are split and decoupled as shown with the APs 150 aand 150 b. The configuration of the radios, at each AP, has changed intotwo different radios, e.g., two 5 GHz radios. Thereinafter, the radiore-router 208 can establish link 152 a between the second set of 4×4radios as shown in stage #2, 140. At this point, the APs can pass databetween two different links 151 and 152.

The radio sever 210 of the RAP 102 may then sever theinterference-problematic link, in stage 510. The radio sever 210 maydiscontinue the link 151 between the two APs as is shown in stage #3142. Thus, only the second link 152 a continues to communicate databetween the two APs on a single 4×4 radio antenna array. In someimplementations, then, the radio re-router 208 can then change thechannel on the other side of the radio link so that the other 5 GHzradio not currently passing traffic is on the same target channel 152A,in stage 512. This change may be done during stage #4 144. In this way,now both portions of the split radios are on the same channel.

The coalesced radio interface 216 may then re-coalesce the radios backto a single MAC instance, in stage 514. The coalesced radio interface216 can re-coalesce the radios as shown in stage #5 146 of FIG. 1G.Then, the coalesced radios may pass data along the single link 154 thatwas changed on the separate separated radios. In this way, the coalescedradios can change channels during the stages 134-146, as shown in FIG.1G.

In another implementation, only one side of the two APs may have acoalesced radio, as may be as shown in FIG. 1H. Here, the changes in theradio links shown in stages 134-146 of FIG. 1H may be done similarly, asdescribed above. For example, in a first stage #1 136, the first AP mayhave coalesced radios 140 a but not at a second AP 104 b. Data may betransmitted from the coalesced radio 148 a to a single radio 148 b. Inthese situations, the radios 148 a are split, as shown in radioconfiguration 150 a and 150 b, as shown in stage #1 138.

The channel 151 is maintained between one of the split radios 150 a andthe second radio 150 b. Thereinafter, the second channel 152 a can beestablished between the second radios while the first channel 151 ismaintained between the second set of radios. The traffic can then besent out to the second link 152 a, and the first link 151 can besevered, as shown in stage #3 142. Then, the second radios can bechanged to the same channel 152, while the radios are still split as isshown in stage #4 144. Thereinafter, the radios on one or both of thedevices may be re-coalesced into the single radio using a single channel154 as shown in stage #5 146.

FIG. 6A shows computing device 600. As shown in FIG. 6A, computingdevice 600 may include a processing unit 610 and a memory unit 615.Memory unit 615 may include a software module 620 and a database 625.While executing on processing unit 610, software module 620 may perform,for example, processes for providing radio interface re-routing asdescribed above with respect to FIGS. 3, 4, and 5. Computing device 600,for example, may provide an operating environment for the controller103, the APs 102/104, or the other devices, however, the controller 103,APs 102/104, and other devices may operate in other environments and arenot limited to computing device 600.

Computing device 600 may be implemented using a Wi-Fi access point, acellular base station, a tablet device, a mobile device, a smart phone,a telephone, a remote control device, a set-top box, a digital videorecorder, a cable modem, a personal computer, a network computer, amainframe, a router, a switch, a server cluster, a smart TV-like device,a network storage device, a network relay devices, or other similarmicrocomputer-based device. Computing device 600 may comprise anycomputer operating environment, such as hand-held devices,multiprocessor systems, microprocessor-based or programmable senderelectronic devices, minicomputers, mainframe computers, and the like.Computing device 600 may also be practiced in distributed computingenvironments where tasks are performed by remote processing devices. Theaforementioned systems and devices are examples and computing device 600may comprise other systems or devices.

FIG. 6B illustrates an implementation of a communications device 630that may implement one or more of APs 102/104, 112, 114, and/or 118,controllers 103, and/or client devices of FIGS. 1A through 1H. Invarious implementations, device 630 may comprise a logic circuit. Thelogic circuit may include physical circuits to perform operationsdescribed for one or more of APs 102/104, 112, 114, and/or 118,controllers 103, and/or client devices of FIGS. 1A through 1H, forexample. As shown in FIG. 6B, device 630 may include one or more of, butis not limited to, a radio interface 635, baseband circuitry 640, and/orcomputing platform 600.

The device 630 may implement some or all of the structures and/oroperations for APs 102/104, 112, 114, and/or 118, controllers 103,and/or client devices of FIGS. 1A through 1H, storage medium, and logiccircuit in a single computing entity, such as entirely within a singledevice. Alternatively, the device 630 may distribute portions of thestructure and/or operations using a distributed system architecture,such as a client-server architecture, a peer-to-peer architecture, amaster-slave architecture, etc.

A radio interface 635, which may also include an analog front end (AFE),may include a component or combination of components adapted fortransmitting and/or receiving single-carrier or multi-carrier modulatedsignals (e.g., including Complementary Code Keying (CCK), orthogonalfrequency division multiplexing (OFDM), and/or Single-Carrier FrequencyDivision Multiple Access (SC-FDMA) symbols) although the configurationsare not limited to any specific over-the-error interface or modulationscheme. The radio interface 635 may include, for example, a receiver 645and/or a transmitter 650. Radio interface 635 may include bias controls,a crystal oscillator, and/or one or more antennas 655. In additional oralternative configurations, the radio interface 635 may use oscillatorsand/or one or more filters, as desired.

Baseband circuitry 640 may communicate with radio interface 635 toprocess, receive, and/or transmit signals and may include, for example,an Analog-To-Digital Converter (ADC) for down converting receivedsignals with a Digital-To-Analog Converter (DAC) 660 for up convertingsignals for transmission. Further, baseband circuitry 640 may include abaseband or PHYsical layer (PHY) processing circuit for the PHY linklayer processing of respective receive/transmit signals. Basebandcircuitry 640 may include, for example, a Media Access Control (MAC)processing circuit 665 for MAC/data link layer processing. Basebandcircuitry 640 may include a memory controller for communicating with MACprocessing circuit 665 and/or a computing platform 600, for example, viaone or more interfaces 670.

In some configurations, PHY processing circuit may include a frameconstruction and/or detection module, in combination with additionalcircuitry such as a buffer memory, to construct and/or deconstructcommunication frames. Alternatively or in addition, MAC processingcircuit 665 may share processing for certain of these functions orperform these processes independent of PHY processing circuit. In someconfigurations, MAC and PHY processing may be integrated into a singlecircuit.

The methods and systems here have distinct advantages and allow formanaging interference issues on a backhaul of a mesh network. The APs inthe network can switch to redundant radio, having a different frequencyband, when interference requires. However, the old link is not severedor torn down until the switch to the new radio link is complete. In thisway, the switch does not cause issues with the client service.

Example of the disclosure, for example, may be implemented as a computerprocess (method), a computing system, or as an article of manufacture,such as a computer program product or computer readable media. Thecomputer program product may be a computer storage media readable by acomputer system and encoding a computer program of instructions forexecuting a computer process. The computer program product may also be apropagated signal on a carrier readable by a computing system andencoding a computer program of instructions for executing a computerprocess. Accordingly, the present disclosure may be embodied in hardwareand/or in software (including firmware, resident software, micro-code,etc.). In other words, example of the present disclosure may take theform of a computer program product on a computer-usable orcomputer-readable storage medium having computer-usable orcomputer-readable program code embodied in the medium for use by or inconnection with an instruction execution system. A computer-usable orcomputer-readable medium may be any medium that can contain, store,communicate, propagate, or transport the program for use by or inconnection with the instruction execution system, apparatus, or device.

The computer-usable or computer-readable medium may be, for example butnot limited to, an electronic, magnetic, optical, electromagnetic,infrared, or semiconductor system, apparatus, device, or propagationmedium. More specific computer-readable medium examples (anon-exhaustive list), the computer-readable medium may include thefollowing: an electrical connection having one or more wires, a portablecomputer diskette, a random access memory (RAM), a read-only memory(ROM), an Erasable Programmable Read-Only Memory (EPROM or Flashmemory), an optical fiber, and a portable Compact Disc Read-Only Memory(CD-ROM). Node that the computer-usable or computer-readable mediumcould even be paper or another suitable medium upon which the program isprinted, as the program can be electronically captured, via, forinstance, optical scanning of the paper or other medium, then compiled,interpreted, or otherwise processed in a suitable manner, if necessary,and then stored in a computer memory.

While certain example of the disclosure have been described, otherexample may exist. Furthermore, although example of the presentdisclosure have been described as being associated with data stored inmemory and other storage mediums, data can also be stored on or readfrom other types of computer-readable media, such as secondary storagedevices, like hard disks, floppy disks, or a CD-ROM, a carrier wave fromthe Internet, or other forms of RAM or ROM. Further, the disclosedmethods' stages may be modified in any manner, including by reorderingstages and/or inserting or deleting stages, without departing from thedisclosure.

Furthermore, example of the disclosure may be practiced in an electricalcircuit comprising discrete electronic elements, packaged or integratedelectronic chips containing logic gates, a circuit utilizing amicroprocessor, or on a single chip containing electronic elements ormicroprocessors. Example of the disclosure may also be practiced usingother technologies capable of performing logical operations such as, forexample, AND, OR, and NOT, including but not limited to, mechanical,optical, fluidic, and quantum technologies. In addition, example of thedisclosure may be practiced within a general purpose computer or in anyother circuits or systems.

Example of the disclosure may be practiced via a SOC where each or manyof the element illustrated in FIG. 1 may be integrated onto a singleintegrated circuit. Such a SOC device may include one or more processingunits, graphics units, communications units, system virtualization unitsand various application functionality all of which may be integrated (or“burned”) onto the chip substrate as a single integrated circuit. Whenoperating via an SOC, the functionality described herein with respect toexample of the disclosure, may be performed via application-specificlogic integrated with other components of computing device 600 on thesingle integrated circuit (chip).

Example of the present disclosure, for example, are described above withreference to block diagrams and/or operational illustrations of methods,systems, and computer program products according to example of thedisclosure. The functions/acts noted in the blocks may occur out of theorder as shown in any flowchart. For example, two blocks shown insuccession may in fact be executed substantially concurrently or theblocks may sometimes be executed in the reverse order, depending uponthe functionality/acts involved.

While the specification includes examples, the disclosure's scope isindicated by the following claims. Furthermore, while the specificationhas been described in language specific to structural features and/ormethodological acts, the claims are not limited to the features or actsdescribed above. Rather, the specific features and acts described aboveare disclosed as example for example of the disclosure.

What is claimed is:
 1. A method comprising: detecting, at a first AccessPoint (AP), inference on a channel with a second AP; checking, by thefirst AP, availability of a redundant radio at the second AP;establishing, by the first AP, a new radio link with the redundant radioat the second AP; rerouting, by the first AP, data traffic over the newradio link to the second AP; and after establishing the new radio link,severing the channel with the second AP.
 2. The method of claim 1,wherein the first AP is a Rooftop AP (RAP).
 3. The method of claim 2,wherein the second AP is a first Mesh AP (MAP).
 4. The method of claim3, wherein, after establishing the new radio link, the RAP reroutestraffic from a queue associated with the channel to the new radio link.5. The method of claim 3, wherein RAP also checks availability of theredundant radio at a second MAP.
 6. The method of claim 5, wherein thefirst MAP communicates to a third MAP.
 7. The method of claim 6, whereinthe RAP instructs the first MAP to reroute traffic to the third MAP. 8.The method of claim 1, further comprising: maintaining, by the firstMAP, an original radio link with a third MAP; and rerouting, by thefirst MAP, data traffic to and from the new radio link to the originalradio link with the third MAP.
 9. The method of claim 1, wherein thechannel and the new radio link are in different frequency bands.
 10. Themethod of claim 1, further comprising: sending, by the RAP, beacons tothe first MAP to determine availability of the redundant radio.
 11. AMulticast Listener Discovery (MLD) device comprising: a memory storage;and a processing unit coupled to the memory storage, wherein theprocessing unit is operative to: establishing a first channel of a firstradio link and a second channel of a second radio link with a second AP;detect inference on the first channel of the first radio link with thesecond AP; check availability of a redundant radio at the second AP;establish a new radio link with the redundant radio at the second AP;reroute data traffic over the new radio link to the second AP; and afterestablishing the new radio link, sever the first channel with the secondAP.
 12. The MLD device of claim 11, wherein establishing the new radiolink with the redundant radio at the second AP comprises detaching aMedia Access Control (MAC) Service Access Point (SAP) from the firstchannel.
 13. The MLD device of claim 12, wherein the processing unitbinds the MAC SAP to the new radio link over the redundant radio. 14.The MLD device of claim 13, wherein the processing unit, after the newradio link is established, sends data traffic only over the new radiolink.
 15. The MLD device of claim 14, wherein the processing unitfurther changes the first channel and reattaches the MAC SAP across thefirst radio link and the new radio link over the redundant radio.
 16. Acomputer-readable medium that stores a set of instructions which whenexecuted perform a method executed by the set of instructionscomprising: detecting, at a first Access Point (AP) in a network,inference on a channel with a second AP, wherein the first AP or thesecond AP communicates with a coalesced radio; splitting the coalescedradio into a first radio and a second radio; checking, by the first AP,availability a redundant radio at the second AP; establishing, by thefirst AP, a new radio link between the first radio and the redundantradio at the second AP; rerouting, by the first AP, data traffic overthe new radio link to the second AP; after establishing the new radiolink, severing the channel with the second AP; and re-coalescing thefirst radio and the second radio.
 17. The computer-readable medium ofclaim 16, the set of instructions further comprising: detaching a MediaAccess Control (MAC) Service Access Point (SAP) from the coalescedradio.
 18. The computer-readable medium of claim 17, the set ofinstructions further comprising: before rerouting the data traffic overthe new radio link, limiting data traffic to a single link between thefirst radio and the redundant radio of the second AP.
 19. Thecomputer-readable medium of claim 18, the set of instructions furthercomprising: changing to the new radio link on the second radio beforecoalescing the first radio and the second radio.
 20. Thecomputer-readable medium of claim 16, wherein only the first AP has thecoalesced radio.